/*
 * Copyright 2002-2009, Haiku, Inc. All rights reserved.
 * Distributed under the terms of the MIT License.
 *
 * Authors:
 *              Michael Pfeiffer
 */
#include "ResourceManager.h"

#include <Debug.h>
#include <Autolock.h>

Resource::Resource(const char* transport, const char* address, const char* connection) 
        : fTransport(transport)
        , fTransportAddress(address)
        , fConnection(connection)
        , fResourceAvailable(0)

{
        if (NeedsLocking()) {
                fResourceAvailable = create_sem(1, "resource");
        }
}


Resource::~Resource() {
        if (fResourceAvailable > 0) delete_sem(fResourceAvailable);
}


bool 
Resource::NeedsLocking() {
        // TODO R2: Provide API to query that information
        // ATM: Print jobs are not processed sequentially
        // if the transport add-on is either "Print To File"
        // or in case of "Preview" printer it
        // is set on R5 to "NONE" IIRC and the Haiku
        // preflet sets an empty string.
        return !(fTransport == "Print to file" 
                || fTransport == "NONE"
                || fTransport == ""); 
}


bool 
Resource::Equals(const char* transport, const char* address, const char* connection) {
        return fTransport == transport &&
                        fTransportAddress == address &&
                        fConnection == connection;
}


bool 
Resource::Lock() {
        if (fResourceAvailable > 0) {
                return acquire_sem(fResourceAvailable) == B_NO_ERROR;
        }
        return true;
}


void 
Resource::Unlock() {
        if (fResourceAvailable > 0) {
                release_sem(fResourceAvailable);
        }
}


ResourceManager::~ResourceManager() {
        ASSERT(fResources.CountItems() == 0);
}


Resource* 
ResourceManager::Find(const char* transport, const char* address, const char* connection) {
        for (int i = 0; i < fResources.CountItems(); i ++) {
                Resource* r = fResources.ItemAt(i);
                if (r->Equals(transport, address, connection)) return r;
        }
        return NULL;
}


Resource* 
ResourceManager::Allocate(const char* transport, const char* address, const char* connection) {
        Resource* r = Find(transport, address, connection);
        if (r == NULL) {
                r = new Resource(transport, address, connection);
                fResources.AddItem(r);
        } else {
                r->Acquire();
        }
        return r;
}


void 
ResourceManager::Free(Resource* r) {
        if (r->Release()) {
                fResources.RemoveItem(r);
        }       
}